Structures of RNA Polymerase Closed and Intermediate Complexes Reveal Mechanisms of DNA Opening and Transcription Initiation.
Structures of RNA Polymerase Closed and Intermediate Complexes Reveal Mechanisms of DNA Opening and Transcription Initiation.
复制标题
DOI：
10.1016/j.molcel.2017.05.010
复制
发表时间：
2017-07-06
期刊：
影响因子：
16
通讯作者：
Zhang X
中科院分区：
文献类型：
--
作者：
Glyde R;Ye F;Darbari VC;Zhang N;Buck M;Zhang X
基因转录通过RNA聚合酶（RNAP）进行。为了发生转录，其中DNA是双链的封闭启动子复合物（RPc）必须异构化成开放启动子复合物（RPo），其中DNA被熔化成转录泡，并且单链模板DNA被递送到RNAP活性位点。使用含有替代σ54因子的细菌RNAP和冷冻电子显微镜，我们在3.8和5.8 ℃下确定了RPc和活化剂结合的中间复合物的结构。我们的结构显示了RNAP-σ54如何与启动子DNA相互作用以启动转录泡形成所需的DNA扭曲，以及激活剂如何与RPc相互作用，导致RNAP和σ54的显著构象变化，从而促进RPo形成。我们建议，DNA熔化是一个积极的过程中启动的RPc和RNAP构象的中间体是显着不同的RPc和RPo。RNA聚合酶封闭复合物（RPc）结构揭示了σ-中间复合物（RPi）结构揭示了AAA激活剂的作用DNA的扭曲和开放在RPc和RPi中开始，然后进入RNAP RNAP构象在RPi中与封闭或开放复合物Glyde et al.报道了σ54依赖的RNA聚合酶（RNAP）封闭复合物（RPc）和中间复合物（RPi）的结构。启动子DNA畸变发生在RPc和RPi中。从RPc到RPi的转变伴随着RNAP和σ54的显著构象变化。AAA激活剂和DNA之间的直接相互作用有助于DNA扭曲。
Gene transcription is carried out by RNA polymerases (RNAPs). For transcription to occur, the closed promoter complex (RPc), where DNA is double stranded, must isomerize into an open promoter complex (RPo), where the DNA is melted out into a transcription bubble and the single-stranded template DNA is delivered to the RNAP active site. Using a bacterial RNAP containing the alternative σ54 factor and cryoelectron microscopy, we determined structures of RPc and the activator-bound intermediate complex en route to RPo at 3.8 and 5.8 Å. Our structures show how RNAP-σ54 interacts with promoter DNA to initiate the DNA distortions required for transcription bubble formation, and how the activator interacts with RPc, leading to significant conformational changes in RNAP and σ54 that promote RPo formation. We propose that DNA melting is an active process initiated in RPc and that the RNAP conformations of intermediates are significantly different from that of RPc and RPo. RNA polymerase closed complex (RPc) structure reveals DNA distortions by σ Intermediate complex (RPi) structure reveals the roles of AAA activator DNA distortion and opening are initiated in RPc and RPi before entering the RNAP RNAP conformation in RPi is significantly different from closed or open complex Glyde et al. report structures of σ54-dependent RNA polymerase (RNAP) closed (RPc) and intermediate (RPi) complexes. Promoter DNA distortions occur in RPc and RPi. Transitions from RPc to RPi are accompanied by significant conformational changes in RNAP and σ54. Direct interactions between AAA activators and DNA contribute to DNA distortions.
登录
查看更多内容
影响因子：
16
作者：
Bose, Daniel;Pape, Tillmann;Burrows, Patricia C.;Rappas, Mathieu;Wigneshweraraj, Siva R.;Buck, Martin;Zhang, Xiaodong
通讯作者：
Zhang, Xiaodong
影响因子：
64.5
作者：
Friedman LJ;Gelles J
通讯作者：
Gelles J
影响因子：
7.7
作者：
Bai, Xiao-chen;Rajendra, Eeson;Scheres, Sjors H. W.
通讯作者：
Scheres, Sjors H. W.
DOI：
10.1073/pnas.1001188107
发表时间：
2010-05-18
影响因子：
11.1
作者：
Burrows, Patricia C.;Joly, Nicolas;Buck, Martin
通讯作者：
Buck, Martin
影响因子：
13.8
作者：
Gruenberg, Sebastian;Hahn, Steven
通讯作者：
Hahn, Steven